I'm dealing with a tricky situation involving some of our users who have an F1 license and both an on-prem Exchange mailbox and an Exchange Online (EXO) mailbox. This dual setup is creating delivery problems. Typically, our hybrid users have only the on-prem mailbox, as the F1 license is meant to provide access to Teams and SharePoint without creating a cloud mailbox. I'm puzzled why some users ended up with a mailbox in the cloud after the F1 assignment, while others did not.
I'm looking for a way to remove the kiosk mailbox linked to these users without losing their Teams and SharePoint history. The workaround we currently employ involves unsyncing the user from Microsoft 365, hard deleting the online mailbox, and then resyncing them from Active Directory. Unfortunately, this process wipes all their Teams history and effectively creates a new Microsoft 365 user. Is there a more elegant solution to remove the kiosk mailbox without taking such drastic measures? I've attempted to remove the Exchange component from the F1 license, but it hasn't resolved the issue for users with existing duplicate mailboxes.
1 Answer
To start, you should try deselecting the Exchange components from the user's license. That’s the first step to clearing up the duplicate mailbox issue. It might help to follow up with the official guide from Microsoft on this topic; it’s crucial to use the command that permanently clears previous mailbox info. Keep in mind that running `Set-User [email protected] -PermanentlyClearPreviousMailboxInfo` will delete everything associated with the Exchange Online mailbox for that user, so be sure this is what you want before proceeding. After you do this, you can then migrate their on-prem mailbox into Office 365 without running into errors.
I've tried that same approach before, but it didn't work for me either. After I disabled the Exchange component, the mailbox remained in EXO unchanged. I even ran the command to clear previous mailbox info, but when I checked the mailbox workloads, it still showed 'Mail, Calendar, Contacts, Substrate.' It's frustrating because we're not migrating these users to online yet; they should just have on-prem mailboxes.